[Optimus One, P500, V General] Bhawan:
Hi,

I am replying to this post just want that other should aware about the facts that Downgrading from 2.3.3 (V20) to 2.2.2 (V10) is possible and is successful using KDZ. You just have to take care of some below Points before flashing:

I AM NOT RESPONSIBLE FOR ANYTHING GOES WRONG TO YOUR DEVICE. TRY ON YOUR OWN RISK

1. Always Use latest driver from LG and make sure that your device is disconnected and any previous version of drivers should be uninstalled from "add and remove programs" using Windows XP SP3 system (Including LGE Virtual Modem,etc. etc. ..!!! (The one who already have latest drivers and clean PC won't find "Virtual Modem" in the device manager, So just Chill :) ) ..Check device manager and uninstall if they still there and also uninstall drivers from other vendors like Nokia, samsung, etc.

2. After uninstalling drivers , restart your system and make sure that your user is an administrator and then install New LG drivers from the LG official website (Just Google== LG P500 drivers ). and Disable LGE Virtual Modem if still its appearing in the device manager.

3. Always make sure that USB Debugging is enabled on the device and your system supports USB 2.0 (High Speed), so notification like "Hi-Speed device is plugged into Non Hi-speed USB" should not appear.!!

3. Extract KDZ_FW_UPD_EN.zip and Install msxml.msi and reboot your system again.!

4. Again you need administrator.!

5. Now Plugged the Device via USB.!, System will install drivers for your device. Wait let the system completes the driver installation .!

6. Unplugged the USB from the phone and Restart the Phone.

7. Wait for the phone to Boot and load completely (Approx 5 minutes).

8. Set Display Brightness timeout to 30 minutes and ensure USB debugging is ON.

9. Plug the device again and keep it at a place where it will not get disturbed. (Also ensure that You have Good working Data Cable, Hope Your Original one is still alive :o )

10. Open KDZ_FW_UPD.exe, select type "3GQCT" and phonemode "DIAG"

11. Click browse and select "V10E_00.kdz" file from where you have download it, I have used Indian version because I have Indian LG O1. (I recommend V10E_00.kdz because i used it twice and it works lika a charm :victory: )

12. Now the Flashing Part .! :fingers-crossed: ...!!. Click Launch Software Update.!

13. The phone will goes to Emergency Mode (Don't panic).! and the flashing process will start.. ! wait for flashing to complete.! Ensure that your system will not goes on Standby or sleep.! And If you are using a Laptop I suggest you to plug in the power first.!

14. I always make my mouse moving while flashing process is in progress. It make me feel better :p. So you can also try this ;)

15. The flashing process may take 5-10 minutes to complete. and you phone will restart itself indicating the offline battery charging screen.!

16. Wait until KDZ prompt "FINISHED" in the end of the log.

17. Unplug the USB and wait for 5 seconds and press and hold Home+VolumeUp+Power simultaneously for Hard resetting the phone .

18. When The screen Shows LG Logo leave the buttons and Hard reset will take half a minute to complete.

19. Wait and Let the device Boots ups completely. (First Boot will take 5 minutes to get you to the lock screen)

20. Done.!! Congratulations.! You are now Downgraded to 2.2.2 . :highfive:

Good Luck :good:

IF anything went wrong during the flashing process or KDZ gave you any error in between the process.! Please DONT pull the battery out from the Phone. Else It will HARD BRICK YOUR PHONE.! And u are not even able to get the phone Power on..I mean Dead! Just Find Support on XDA and try and try again.! (Also suggest you to do not unplug the data cable, it may also lead to HARD brick the phone.)

In this situation ensure that you have a right flashing KDZ file. and IF you have the right one use different "phonemode" like Emergency, Emergency_CS, etc and try and try again.!

IF still wont work try to shake your phone and touch the screen again and again and try to launch the software upgrade

If still device is not responding try lgmdp method and try to flash a recovery and Image.

If nothing works restart you system and then again launch the software update in emergency mode.! (This option works for me once but i recommend you to try it as a last choice)

Don't pull the battery out and ask for support on xda.! Might be someone save your phone's life.

If the phone is still stucked you have to get it to the service centre. (If your phone is in warranty they will replace the PCB free of cost)